TITLE:
Nitrogen and Boron Doped Diamond Like Carbon Thin Films Synthesis by Electrodeposition from Organic Liquids and Their Characterization
AUTHORS:
Sunita Kundoo, Satyajit Kar
KEYWORDS:
Non-Crystalline Materials; Thin Films; Infrared Spectroscopy; Electrical Conductivity; Optical Properties
JOURNAL NAME:
Advances in Materials Physics and Chemistry,
Vol.3 No.1,
March
27,
2013
ABSTRACT: Thin films of amorphous diamond like carbon (a:DLC) were deposited by
using a novel technique. By electrodeposition from methanol-camphor solution
thin a:DLC films were deposited on non-conductive glass substrates and also on
high resistive Si substrates, by using a fine wire mesh electrode, at atmospheric
pressure and temperature below 350 K. Thin films of a:DLC were doped by
incorporation of nitrogen (a:N-DLC) and boron (a:B-DLC) using urea and boric
acid with methanol-camphor solution respectively during the electrodeposition
process. From transmittance measurements in the UV-VIS-NIR region, the optical
energy band gap of about 1.0 eV for undoped a:DLC film, 2.12 eV for a:N-DLC and
2.0 eV for a:B-DLC films were determined. The spectra showed high transparency
in the visible and NIR region. Fourier transform infrared spectroscopy (FTIR)
measurements showed the appearance of various C-H and C-C
bonding in the spectrum of undoped amorphous DLC film and confirmed C-N and C=N
bond formation in a:N-DLC film. From the temperature variation of d.c.
conductivity studies, the activation energies were determined and found to be
0.75 eV, 0.32 eV and 0.58 eV for undoped a:DLC films, a:N-DLC and a:B-DLC films
respectively. Electrical resistivity at room temperature was reduced by the
doping effect, from 109 Ω-cm for undoped films to 107 Ω-cm
for nitrogen doped films and 108 Ω-cm for boron doped films.